Process for the production of endless intaglio printing forms



May 30, 1933. K. WOLFSOHN 1,911,254

PROCESS FOR THE PRODUCTION OF ENDLESS INTAGLIO PRINTING FORIS Fua Aug. 25, 1930 Patented May 30, 1933 PATENT orrica m'r WOLFSOHN, OI SCEOENEBEM NEAR BERLIN, GERMANY, ASSIGNOR '10 ROTO- PHO'I' AA FUR GRAI'HISOHE INDUSTRIE, OI BERLIN, GERMANY, A. CORPORATION OF GERMANY PROCESS FOR THE PRODUCTION OF ENDLESS .INTAGLIO PRINTING FORMS Application filed August 25, 1930, Serial No.

In my copending application Ser. No.

h 477,604, filed simultaneously herewith, is described a process for the production of end-. lessly etc ed intaglio printing forms by transferring the resist covering on to a printin cylinder in a single operation, such requiring the utilization 0 carbon coatin s which are easily detachable from their bac in i1 contradistinction thereto the present invention while it embodies certain features described in said copending application, eliminates the necessity for employing easily detachable carbon coatings. The present invention offers thus the advantage that the ordinary kind of carbon apers may be used in the performance of t e process described in said application.

M improved process may be performed in the ollowing manner:

The edges of a carbon sheet, i. e. asensitized gelatine or other film on a suitable backing, larger in size than the circumference of the copper cylinder, are marked in the middle to correspond to the length and width of the intaglio printing cylinder for the purose of serving as register marks for the simiarly marked design. The design is 'now placed on the carbon sheet in'such manner that allre 'ster marks tall and then the copy is ma e. Thereafter, t e exact circumference and width of the printing cylinder are ruled out on the carbon sheet measured from the register mares, and then, one of 85 the resulting margins is out ofl, and an inci-.

0 treatedgmargin serves as a gripping edge and is' made non-adhesive, whic accomplished by pasting a strip of paper over the coating or by applying a coat of varnish; previous to this, the other mar have been may be nicked. The gripping edge w ich has been 477,608, and in Germany August 27, 1929.

made in aforesaid manner is utilized in the usual way to provide a start for the transfer Operation.

The invention will be further described in connection with the accompanying drawing which illustrates by way of example a preferred manner of carrying out the same. In said-drawing,

Fig. 1 is a plan view of a transparent sheet having thereon the pattern which is to be etched on the printing cylinder;

Fig. 2 is a similar View of the sheet of sensitized film, commonly called carbon tissue or carbon sheet;

Fig. 3 is a section through the carbon sheet, and indicates the complete severing of one superfluous marginal portion and the partial severing of the other after the sheet as been exposed;

Fig. 4 is a view similar to Fig. 3 and shows the non-adhesive coating on the gripping edge portion whereby the latter is prevented from sticking to the printin cylinder;

Fig. 5 shows the carbon sheet asit is beingvintroduoed into the transfer device;

ig. 6 shows the sheet partly mounted upon the copper printin c linder;

Fig. 7 is a plan view 0 Fig.6 illustrating the removal of the gripping edge from the carbon sheet, and

Fig. 8 is an end view of a cylinder having the carbon sheet applied thereon, and a varnish coating protecting the seam against the entr of water.

T e carbon or equivalent sheet, shown in Fig. 2, is longer than the circumference of the copper or other cylinder upon which the endless intaglio pattern is to be roduccd, and is provided with markings w ich indicate the center lines alon both the width and circumference of the mtaglio rinting cylinder. The so marked sheet, in w ich the surface 1', 2 3, 4 corresponds exactly to the surface of the endless printing form or cylinder,is then accurately placed upon the pattern sheet shown in Fig. 1 which is provided with similar markings. The copy is then made upon the carbon sheet 5 b exposing the sheets on known manner. easuring now from the center markings, the exact surface 1, 2, 3, 4 of the printing form-is now indicated on the carbon sheet 5, the distance between the lines 1, t and 2, 3 corresponding exactly to the circumference of the copper cylinder. The superfluous portion 5' is now cut 0!! by means of almife 6, as indicated in Fig. 3, alon the line 1 2, while upon the opposite side, t e layer 718 out through by means of the knife 6 without, however, injuring the film carrier 8. There thus remains a superfluous piece 5" which is connected with the main part 5 only through the film carrier 8. The carbon film on the piece 5" is then covered with a iece of aper or varnish coating 11 (Fig. 4? to ren er it inca able of adhering to the printing form or cy inder. This coated and partial y severed portion 5'.' rovides a gripping'edge with the aid of w ich the sheet 5 is accurately introduced-into the transfer device, a known form of which is shown in Fig. 5, wherein the copper cylinder is shown at 12 and the transfer cylinder, which may be of rubber, is shown at 13. As soon as. the transfer device is set into motion, the carbon sheet 5, whose colored gelatinous coating has been made sticky and adhesive by moistening, as by means of steam, is drawn into the transfer device in correct alignment with the printing cylinder. As soon as the ifiping ed e has passed to the other side 0 t e tran er device, the sticky carbon layer clings to the copper cylinder 12, so that the gripping edge f t e is no longer necessa This phase 0 process isv shown in Fig. 6. The superfluous edge is then removed, as shown in Fig. 7 which shows a plan v ew of Fi 6 with the cylinder'lB- removed. To, faci itate the removal of the iece 5", the carrier or backingv sheet 8 may partially cut or scratche along the line 3, 4 by theknife 6. Upon fur-' ther rotation of the transfer device, the sheet 5 is relied upon the cylinder 12 until the edges 1, 2 and 3, 4 meet whereupon the sheet completely surroundsthe cylinder.

It will be readily understood that the gripping edge need not necessarily be part of the carbon sheet itself. For example, the carbon sheet may be of the exact size of the copy and a gripping edge may be produced by pasting on a strip with provision-for easy removal, e. g. perforation. This grip'ii g edge is likewise utilized as described a ove and the transfer operation is begune, g. by moistening theintaglio printing cylinder. The gripping edge is torn ofl', asdescribed, when the transfer operation is inprogress; thus, both the edge which had the security edge aflixed and its parallel edge hood of the seam as com ared to other portions' of the cylinder. T is so-called underwash is a serious drawback which, according to the resent invention maybe overcome by app ying a protective waterproof coating 14 (see Fig. 8) of e. g. varnish or caoutchouc before developing operations are commenced, thus preventing this undesirable'action of the heated water, used as develo ing agent, and, when the heated water as acted sufliciently a solvent is aplied for the removal of t e rot'ective coating and the interrupted deve opment is continued and completed. Finally the endless intaglio printingform is etched in known manner.

Having now particularly described and ascertained .the nature of the present invention and the manner in which it is to be performed I declare what I claim is the carbon sheet after the p eted, and etching the print- 2. The improvement in the 'art of producing intaglio less desi rom bodies of rotat1on, such as meta ic cylinders by a single transfer, which comprises copying the whole design upon a carbon sheet larger than such esign toprovide a superfluous ortion at one marginal edge of the design a a ted to serve as a gripping portion, partia ly severing said gripping portion to facilitate its sub- A neat complete removal, covering said gripping ortion with a non-adhesive coatmg, .trans erring the ex osed sheet onto a printing form with the aid of said gripping portion, removing the latter after the transer has commenced, developing the finished transfer, and etching the printmgforin.

3. The process as set forth in claim 5 wherein the carbon sheetis of a len equal to the periphery of the printing cm, the gri ping portion being pasted to said sheet an made easily removable therefrom.

4. The improvement in the'art of producing intaglioprintin forms having an endless design from b ies of rotation, such as metallic cylinders, bya sin le transfer, which comprises copying the w ole -design upon printing forms having an endiss' a carbon sheet, providing the latter with an easily detachable, non-adhesive gripping portion, transferring said sheet upon a printing form with the aid of said gripping por- 5 lion, removing the latter after the transfer has commenced, coating the seam with a waterproof material, developing the film, removing the waterproof coating, continuing the developing and finally etching the print- 10 ing form.

In witness whereof I si ned my name hereinto on this 13th day of Kugust, 1930.

KURT \VOLFSOHN.

CERTIFICATE OF CORRECTION.

Patent No. 1,911,254. May 30, 1933.

KURT WOLFSOHN.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 2, hne 12], claim 3. (or the ciaim reference "5" read "I"; and that the said Letters Patent should be read with this correction therein that the same may onform to the record of the case in the Patent Office.

Signed and scaled this 24th day of October, A. I). 1933.

I". M. Hopkins (Seal) Acting Commissioner of Patents.

a carbon sheet, providing the latter with an easily detachable, non-adhesive gripping portion, transferring said sheet upon a printing form with the aid of said gripping por- 5 lion, removing the latter after the transfer has commenced, coating the seam with a waterproof material, developing the film, removing the waterproof coating, continuing the developing and finally etching the print- 10 ing form.

In witness whereof I si ned my name hereinto on this 13th day of Kugust, 1930.

KURT \VOLFSOHN.

CERTIFICATE OF CORRECTION.

Patent No. 1,911,254. May 30, 1933.

KURT WOLFSOHN.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 2, hne 12], claim 3. (or the ciaim reference "5" read "I"; and that the said Letters Patent should be read with this correction therein that the same may onform to the record of the case in the Patent Office.

Signed and scaled this 24th day of October, A. I). 1933.

I". M. Hopkins (Seal) Acting Commissioner of Patents. 

